Skeletal Muscle Contractile Function in Heart Failure With Reduced Ejection Fraction-A Focus on Nitric Oxide

Supplementation with l-arginine and nitrates vs age and individual physiological reactivity

Ageing is a natural ontogenetic phenomenon that entails a decrease in the adaptive capacity of the organism, as a result of which the body becomes less adaptable to stressful conditions. Nitrate and nitrite enter the body from exogenous sources and from nitrification of ammonia nitrogen by intestinal microorganisms. This review considers the mechanisms of action of l-arginine, a known inducer of nitric oxide (NO) biosynthesis, and nitrates as supplements in the processes of ageing and aggravated stress states, in which mechanisms of individual physiological reactivity play an important role. This approach can be used as an element of individual therapy or prevention of premature ageing processes depending on the different levels of initial reactivity of the functional systems. A search was performed of the PubMed, Scopus, and Google Scholar databases (n = 181 articles) and the author's own research (n = 4) up to May 5, 2023. The review presents analyses of data on targeted treatment of NO generation by supplementation with l-arginine or nitrates, which is a promising means for prevention of hypoxic conditions frequently accompanying pathological processes in an ageing organism. The review clarifies the role of the individual state of physiological reactivity, using the example of individuals with a high predominance of cholinergic regulatory mechanisms who already have a significant reserve of adaptive capacity. In studies of the predominance of adrenergic influences, a poorly trained organism as well as an elderly organism correspond to low resistance, which is an additional factor of damage at increased energy expenditure.

CONCLUSION

It is suggested that the role of NO synthesis from supplementation of dietary nitrates and nitrites increases with age rather than from oxygen-dependent biosynthetic reactions from l-arginine supplementation.

The Importance of Diaphragmatic Function in Neuromuscular Expression in Patients With Chronic Heart Failure

Chronic heart failure (CHF) is a set of symptoms and physical manifestations caused by the inability of the heart to perform its normal contractile function and satisfy the blood needs of all organs. This dysfunction leads to a non-physiological adaptation of all body systems, including the skeletal muscles and the diaphragm. The myopathy found in patients brings symptoms such as fatigue and intolerance to exercise, with an entity not always attributable to cardiac function. Neuromuscular incoordination is one of the symptoms related to CHF, causing an increased risk of mortality and hospitalization. The article reviews diaphragmatic adaptation in the presence of CHF and seeks to emphasize the importance of the diaphragm in understanding skeletal muscle incoordination in patients.